Sarcomatoid hepatocellular carcinoma mimics hepatic abscess on contrast‐enhanced ultrasound

Key Clinical Message Sarcomatoid hepatocellular carcinoma (SHCC) is a rare subtype of hepatocellular carcinoma characterized by abdominal pain or persistent fever with an inflammatory reaction. Here, we report a case of SHCC mimicking hepatic abscess described by not only ultrasonography but also computer tomography. SHCC is a rare subtype of hepatocellular carcinoma characterized by epithelial and mesenchymal tumor features with sarcomatoid morphology. Here, we report a case of SHCC described by ultrasonography and computer tomography as well as confirmed by pathological examination.

Sarcomatoid hepatocellular carcinoma (SHCC), is a rare subtype of hepatocellular carcinoma characterized by epithelial and mesenchymal tumor features with sarcomatoid morphology, whose incidence is only 5% of hepatocellular carcinoma. 1Compared with hepatocellular carcinoma, SHCC has more rapid tumor growth and poorer disease progression.However, SHCC is easily misdiagnosed and delays the optimal treatment due to the clinical and imaging features being similar to hepatic abscesses.Here, we present a case image, including routine abdominal ultrasound, contrast-enhanced ultrasound, plain computer tomography, and enhanced computer tomography, of SHCC that mimics hepatic abscesses.
A 71-year-old male patient presented to our hospital with a fever of unknown origin for 1 month, whose temperature is approximately 38°C.Physical examination revealed a right epigastrium slight tenderness.Laboratory tests revealed hypersensitive C-reactive protein of >5.00 mg/L, routine C-reactive protein of >200.00 mg/L, white blood cell of 21.36 × 10 9 /L, neutrophils of 18.43 × 10 9 /L, activated partial thromboplastin time of 45.30 s, fibrinogen quantification of 8.21 g/L, hepatitis B virus surface antigen of <0.01 IU/mL, hepatitis B virus surface antigenantibody of 32.12 mIU/mL, hepatitis B virus e antigen of 0.439 S/CO, hepatitis B virus e antigen-antibody of 1.59 S/ CO, and hepatitis B virus core antigen-antibody of 6.41 S/ CO, alpha feto protein of 50.98 ng/mL.
Initially, routine abdominal ultrasound explored a hypoechoic mass located in the right hepatic lobe with irregular anechoic areas internally (Figure 1).Additionally, a contrast-enhanced ultrasound indicated a mass with rapidly high peripheral enhancement during the arterial phase and with low peripheral enhancement during the portal venous phase without internal enhancement throughout all the phases (Figure 2).Furthermore, the mass had low density with internal cystic degeneration on plain computer tomography and obvious peripheral lar carcinoma characterized by abdominal pain or persistent fever with an inflammatory reaction.Here, we report a case of SHCC mimicking hepatic abscess described by not only ultrasonography but also computer tomography.SHCC is a rare subtype of hepatocellular carcinoma characterized by epithelial and mesenchymal tumor features with sarcomatoid morphology.Here, we report a case of SHCC described by ultrasonography and computer tomography as well as confirmed by pathological examination.

K E Y W O R D S
computer tomography, hepatocellular carcinoma, Sarcomatoid, ultrasonography enhancement with no internal enhancement on enhanced computer tomography (Figure 3).Ultimately, the patient underwent a surgical mass excision, and an SHCC diagnosis was confirmed (Figure 4).No recurrence or metastasis was found during the 5-month postoperative follow-up.
According to the previous literature, the patient of SHCC has abdominal pain or persistent fever with an inflammatory reaction due to infection and necrosis in malignancy.Routine abdominal ultrasound and plain computer tomography reveal the mass is diffuse liquefactive necrosis with or without metastasis or portal and  hepatic vein thrombosis. 2 Contrast-enhanced ultrasound and enhanced computer tomography observe the mass with irregular, thick, circular, and high enhancement. 3owever, the evidence of SHCC remains too deficient to differentiate it from hepatic abscesses, and thus further research is necessary.

F I G U R E 1
Routine abdominal ultrasound of sarcomatoid hepatocellular carcinoma.(A) Grayscale ultrasound showed a cystic-solid mass (arrow) located in the right hepatic lobe that was irregular, ill-defined, inhomogeneous, and approximately 56 × 53 × 44 mm in size.(B) Color Doppler flow imaging showed no blood flow signal inside the mass (arrow).

F I G U R E 2
Contrast-enhanced ultrasound of sarcomatoid hepatocellular carcinoma.(A) In the early arterial phase, the mass (arrow) rapidly enhanced beginning in the 12th second.(B) In the arterial phase, the mass (arrow) was high peripheral enhancement with no internal enhancement in the 15th second.(C) In the portal phase, the mass (arrow) was washed out in the 129th second.